Bearing provided with a carrier surface for moving a platform on an air cushion

ABSTRACT

The invention relates to a bearing provided with a carrier surface along which a platform ( 6 ) with people or other loads can move on an air cushion, preferably without a motor, wherein the air cushion can be maintained without too great an effort. According to the invention, the form thereof is that of a box ( 1 ) with a perforated surface for the discharge of air. The openings in the surface are provided with automatic valves ( 5 ) which are connected to the inner area of the box ( 1 ). The cavity on one side of the moveable element of the valve ( 5 ) is connected to the opening on the upper side of the box ( 1 ). The cavity on the other side of the moveable element of the valve ( 5 ) is connected to the outer air. The openings on the side of the valve housing are connected to the inner area of the box ( 1 ).

The invention pertains to conveying means on an air cushion and is defined for active recreation and sports activities of people with the use of platforms on an air cushion, preferably without a motor, and for the movement of the platforms on the air cushion with people and loads in pedestrian and spa areas of cities.

Conveying means in the form of devices on an air cushion, comprising a centrifugal blower and a compressor with a power drive for pressing the air under the device housing (Korytow N. W., Schiffe und Luftkissengeräte, M., 1964) are known. The device with blower and power drive is freely displaceable; however, its large mass and high costs as well as the high noise level limit its use for active recreation and sports.

Devices are known, wherein, for the creation of an air cushion, the immovable bearing provided with the carrier surface comprises a large number of openings for the passage of the air, which is pressed into the cavity within the bearing. Such devices are used, for example, in mechanical engineering and in fine mechanics devices in the form of aerostatic and gas-dynamic bearings for securing a plane parallel movement or a rotary motion with low friction loss (Pelpor D. S., Gyroskopische Geräte und Autopiloten. M., 1964). The said devices are installed in machine tools and precision equipment and have specific construction features, which prevent their use in the technical area of the application.

A device, based on which the table game “Airhockey” was made, is also known. This device comprises a carrier surface in the form of an entire small table with edges. Air is blown within the small table. The air discharges through openings, which are evenly arranged on the table surface. Thanks thereto, a thin air cushion is formed between a light disk, which imitates a puck, and the table surface. For this reason, the disk moves on the table surface virtually without friction and is subject to only a small air resistance. The disadvantage of the device lies in a relatively large air consumption for the realization of an air cushion effect.

An invention, which is defined for facilitating the load displacement within railway cars and automobiles, in storage, but also for conveying heavy cardboard and paper packages in businesses, is most similar to the filed device. In this device, the air cushion is provided between the load underside and the bottom by supplying compressed air through ball valves being mounted in the carrier surface. A system consisting of dense valves, pipes, and flaps for supplying air from the compressor to the ball valve groups being mounted in the bottom, is provided below the carrier surface. The valves in the bottom are arranged in such a way that the balls partially discharge onto the bottom surface. With a direct mechanical impact of the moving load onto the movable element of the valve, i.e. the ball, the load overcomes the effect of the spring and of the compressed air and opens an output for the air into the area between the bottom and the load [U.S. Pat. No. 1,021,040 A, MPK B 60 V 3/04, published Feb. 23, 1966, and patents regarding this invention in other countries: U.S. Pat. No. 3,235,099 (A1), BE 653651(A), DE 1285400 (B1)]. The instant device can be considered a prototype.

The disadvantage of this prototype is that, for the opening of the valves to supply air for the air cushion underneath the load, it is necessary to push the movable element of the valve downward directly through the load or the load pallet. This does not represent a considerable disadvantage for the use quoted in [U.S. Pat. No. 1,021,040 A, MPK B 60 V 3/04, published Feb. 23, 1966, and patents regarding this invention in other countries: U.S. Pat. No. 3,235,099 (A1), BE 653651 (A), DE 1285400 (B1)], because the loads only move a few meters and only with low speed. However, such a device is not suitable for a use of such a technical solution in a bearing provided with a carrier surface for platforms on an air cushion defined for active recreation and sports. The mechanical contact of the platform with a large number of ball valves leads to a considerable increase of frictional losses, decreases the ability to control the platform, and causes the feeling that the platform floats on the carrier surface to vanish.

The object of the instant invention is the production of a bearing provided with a carrier surface, along which a platform with people or other loads can move on an air cushion, preferably without a motor, with minimal energy input for maintaining the air cushion.

The object aimed at by the invention is characterized in that the bearing provided with the carrier surface for moving a platform on an air cushion is embodied in the form of a box with a perforated surface for the discharge of air, which is pressed into the inner area of the box, whereby the openings on the surface of the box are connected with the inner area of the box via automatic valves, whereby the cavity on one side of the movable element of the valve is connected to the opening on the surface of the box. The cavity on the other side of the movable element of the valve is connected to the outer air, which is not exposed to the pressure of the air cushion, and the openings on the side of the valve housing are connected to the inner area of the box.

The movable element of the automatic valve is embodied in the form of a differential piston, whereby the cylinder on one side of the large piston is connected to the opening on the surface of the box, and the cylinder on the other side of the large piston is connected to the outer air, which is not exposed to the pressure of the air cushion, whereby the openings on the side wall of the cylinder on one side of the large piston and of the cylinder on the other side of the large piston are connected to the inner area of the box.

The area above the box is connected to the inner area of the box via air nozzles.

The box of the bearing is embodied by hollow modules, the adjoining side surfaces of which allow a free circulation of the air through the inner area, whereby the valves are arranged within the modules in such a way that they are mechanically connected to the carrier surface of the box via their upper part, and the lower part of the valves is mechanically connected to the bottom of the box.

The box of the bearing is embodied in the form of a conveying route with predetermined construction for moving platforms on an air cushion with people and loads thereon, whereby the box is embodied by hollow modules or in the form of a scaffolding, which is covered with a soft air-impermeable material, for example an industrial fabric or a polymer foil.

FIG. 1 illustrates a general view of the bearing provided with the carrier surface for the platform on an air cushion with the following details and components: 1—carrier surface of the bearing in the form of a box, consisting of modules; 2—bottom of the bearing; 3—inner area of the bearing; 4—centrifugal blower; 5—automatic valve; 6—platform for the air cushion. Generally, the platform 6 does not have its own blower and its own power drive for creation of an air cushion.

FIG. 2 illustrates a cross-sectional view of the bearing provided with the carrier surface with the following details: 7—openings in the side wall of the automatic valve; 8—movable element of the valve (piston); 9—elastic element (spring); 10—cavity below the platform; 11—air nozzle.

FIG. 3 illustrates an automatic valve with the movable elements in the form of a differential piston, whereby: 12 and 13—large or small piston of the differential valve; 14—valve for leading the air to the small piston; 15—spring of the differential valve.

The bearing provided with the carrier surface (FIG. 1) consists of a box with an outer carrier surface 1, being connected or fastened to a field in the form of a drawn path with predetermined configuration. The bearing of the carrier surface has a bottom 2. During operation of the device, air is supplied to the inside of the bearing via a centrifugal blower 4. Thanks to the operation of automatic valves 5, the air discharges from the inner area 3 to the carrier surface 1 of the bearing only in those locations, where the platform 6 is located at the given point in time. The valve housing 5 mechanically connects the carrier surface 1 and the bottom 2 of the bearing. Drainage valves for discharging the condensate can be provided in the bottom (not illustrated in the figures).

As can be seen from FIG. 2, the pressure of the air cushion of the platform acts upon the piston 8 through the openings in the carrier surface 1. The piston diameter 8 and the characteristics of the spring 9 are chosen in such a way that the force of the pressure of the air cushion onto the piston is always higher than the compression force of the spring. The piston, which compresses the spring 9, drops downward and opens the opening 7 in the side wall of the valve body. Under overpressure, the air discharges through the opening from the inner area 3 of the bearing onto its carrier surface 1, and reaches below the platform 6.

Thanks to the large number of open valves 5, which are under the influence of the pressure of the air cushion of the platform at the given point in time, a large air flow reaches from the inner area of the bearing under the platform. A dynamic balance between the inflow and the use of air is thereby maintained below the platform. It is obvious that the thickness of the air cushion depends on the productivity of the centrifugal blower 4 (FIG. 1). For establishing an air cushion at the start of the platform, the area above the box is connected to the inner area of the box via air nozzles 11 (their designation is described below).

It can be seen in FIG. 3 that in the automatic valve, air under overpressure located in the inner area of the bearing surface can also be used as an elastic element. For this purpose, the movable element of the valve is embodied in the form of a differential piston, consisting of a large and a small piston 12 and 13. When the platform is above the valve, the pressure of the air cushion moves the differential piston downward, whereby it overcomes the pressure of the air on the small piston 13 and the counteraction of the spring 15. The air is supplied to the small piston 13 of the valve through a channel 14 from the inner area of the bearing. The openings 7 open, and the air from the inner area of the bearing discharges under the platform. In the differential valve, the spring 15 has a low stiffness, because it is essentially defined for closing the valve when the blower is turned off.

During a movement of the platform, the valves in the bearing surface are automatically opened by the platform under the impact of the pressure of the air cushion, and the platforms behind it open under the impact of the elastic element, as soon as the pressure reaches the bearing surface in the atmosphere. As can be seen from the above description, the valves open and close automatically, without direct mechanical contact with the platform.

The platform on the air cushion can stand immovable on a horizontal carrier surface only when an exact symmetrical discharge of air takes place along the periphery of the platform. This is possible, when the vector of the mass center of the platform with the load and the vector of the pressure of the air cushion lie on a vertical axis. For a horizontal movement of the platform, the platform must thus be inclined in the direction of the desired movement. The quantity of the acceleration of this movement depends on the mass of the platform, its inclination, and the quantity of the air pressure in the air cushion. Simultaneously, the maximum inclination of the platform is determined by the thickness of the air cushion and the measurements of the platform. The necessary power of the centrifugal blower, which supplies air to the bearing provided with the carrier surface, is calculated based on the known equations of the aerodynamics of the subsonic flows and in consideration of correction coefficients.

Specifically, in the simplest application of the platform on an air cushion, a certain discharge of air through the valves, which are arranged on the carrier surface of the bearing, is permitted. In this case, the platform is lifted onto the air cushion in the following manner during its start. When, at the starting time, the platform is located on the carrier surface, the cavity 10 below the platform (FIG. 2) fills with air within a few seconds, and the air discharges through the leakages in the closed valves. However, the discharge of the air from the cavity 10 is prevented by means of a soft sealing of the platform at its periphery. The speed of the discharge of the air below the platform is thus slower than the inflow of air through the slits in the dozens of valves, which are located in the carrier surface below the platform.

When a certain pressure is reached below the platform, the automatic valves are opened, the inflow of air below the platform is increased, and the platform is lifted above the carrier surface.

However, it is reasonable to use valves with a minimal discharge for a bearing provided with a large carrier surface or a large expansion. This is necessary for lowering the energy consumption for the supply of air into the inside of the bearing provided with a carrier surface. With a low discharge of air through the valves, its required amount for starting the platform is ensured by the supply of air through calibrated air nozzles 11 (FIG. 2), which are arranged in the carrier surface of the bearing. The nozzles can thereby be mounted in the carrier surface in two ways:

-   -   a) for the start of the platform, nozzles are arranged at         arbitrary locations in such a way that no less than one nozzle         is present on a surface unit of the bearing equal to the normal         projection of the air platform on the carrier surface,     -   b) for the start of the platform, groups of air nozzles are         arranged at the corresponding locations of the carrier surface,         only at the locations provided therefor.

With regard to the additional energy input for the supply of air into the inside of the bearing, both types of the configuration of the air nozzles are acceptable. It is obvious thereby that the second type is more economical.

The embodiment of the bearing provided with a carrier surface for platforms on air cushions with a simultaneous use of housings of automatic valves as power elements of the construction, which connects the surface of the bearing and its bottom, decreases the material expenditure and the costs of the bearing.

The production of the bearing provided with a carrier surface in the form of a scaffolding, which is covered with an air-impermeable industrial fabric or construction polymer films, which are stable to light, enable a simplification of the conveyance and of the assembly of the bearing provided with a large surface and a decrease of the material expenditure.

As can be seen from the documents of the application, the bearing provided with a carrier surface consists of a small number of details, which can be produced with the methods of mass production, for example, by means of plastic die-casting, extrusion with formation of compressed air, compression, etc..

The calculations confirm that the device is powerful and that the object of the invention is achieved. 

1. A bearing provided with a carrier surface (1) for moving a platform (6) on an air cushion, whereby the bearing has the form of a box with a perforated surface and the perforated surface has openings in the carrier surface (1) of the box for the discharge of air, which is pressed into the inner area of the box, whereby the openings in the carrier surface (1) of the box are connected to the inner area of the box via automatic valves, and whereby each of the automatic valves comprises a movable element, which is pressed against the openings in the carrier surface (1) of the box by a spring (9, 15), characterized in that the movable element is a piston (8, 12) which moves in a valve housing (5), and in that valve openings (7) are arranged near the openings in the carrier surface (1) in a side wall of the valve housing (5), such that the piston (8, 12) releases the valve openings (7) when the automatic valve is open, so that air can escape from the inner area of the box through the valve openings (7) and the openings in the carrier surface (1) of the box.
 2. The bearing according to patent claim 1, characterized in that the movable element is a differential piston.
 3. The bearing according to patent claim 2 characterized in that the differential piston consists of a large piston (12) and of a small piston (13), whereby the large piston (12) is pressed against the opening in the carrier surface (1) of the box by the air in the inner area of the box and the small piston is pressed against the opening in the carrier surface (1) of the box by the spring (15) and the air in the inner area of the box.
 4. The bearing according to one of patent claims 1 to 3, characterized in that the box of the bearing is embodied by hollow modules, the adjoining side surfaces of which allow a free movement of the air in the inner area, whereby the valves within the modules are arranged in such a way that they are mechanically connected to the carrier surface (1) of the box, and that the lower part of the valves is mechanically connected to the bottom of the box.
 5. The bearing according to patent claim 4, characterized in that the bearing is embodied in the form of a conveying route with predetermined construction for the movement of platforms on an air cushion for transporting people and loads, whereby the box is embodied by hollow modules or in the form of a scaffolding, which is covered with a soft air-impermeable material, for example an industrial fabric or a polymer foil.
 6. The bearing according to patent claim 4, characterized in that the air nozzles (11) for the start of the platforms (6) are arranged at defined locations in the carrier surface (1). 